Developing spectrophotometric method for Carbamazepine (antiepileptic drug) determination through preparation and Characterization of Fe(III) Complex With Mixed Ligand Containing Carbamazepine and Salicylaldehyde

Abstract

The research includes developing an easy and sensitive analytical
spectrophotometric method to determine Carbamazepine (CBZ) ,which consider
among antiepileptic and antisezuires drugs.
The method was depended on preparation of mixed ligand
[dibenzo[b,f]azepine-5[N-(O-hydroxybenzyliden)] amide from CBZ reaction with
salicylaldehyde. It was found that the ligand has an ability to form colored complex
with ferric ion at ratio (2:1) L: M , that have λ max at 524 nm in aqueous solution at
pH 6.5. The optimum conditions for Complexing CBZ with ferric ion including the
volume of ferric solution (1.2 ml), time period (10 minutes) and temperature ranges
(30-35 o C) were identified. The structural formula of the formed complex was
proposed due to the spectroscopic study including UV and IR spectrums. Stability
constant of CBZ-Fe complex in aqueous solution was (1.3x109 L2. mol-2), and the
complex was stable for 24 hours in the aqueous solution. Calibration curve obeyed
the Beer’s law at (1.0 -25) mg.l-1 for CBZ with a correlation coefficient (r = 0.9996).
The molar absorptivity coefficient was 2.17 × 103 l. mol-1cm-1. The statistical
processing of the results showed that relative standard deviation 1.1%, the average
of relative error 1.42%, while method recovery is 100.2 %. The detection limit was
0.25 mg.l-1 and limit of quotation was 0.83 mg.l-1. The method reveals high accuracy
and precision. This method is characterized by no need for solvent extraction. The
proposed method was applied on samples of drugs and plasma which provided
encouraging resultants.